Into the Peatlands (eBook)

Creation: What Is Peat?

Peatlands are not dry land. Neither are they wetlands. They are different.

Difference has not always been – and sadly is often still not – appreciated, whether that is a natural habitat, like the bog – the word ‘bog’ has its origin in the Gaelic word bogach – or the people who live on or by it. The idea expressed in the passage above that you ‘cross the threshold of civilisation’ by entering the moor has led not only to ‘uncivilised’ behaviour toward this different land but also to the people of that land – ‘heathens’ supposedly come from the heath.

In early spring I am standing on Kirkconnel Flow in the far southwest of Scotland. Peat-brown water covers the mosses and grasses on which I am walking but, having stopped, it is gradually flooding over my wellies. I am steadily sinking into the ground.

Nearby on 16 November 1771 part of Solway Moss on the Scottish/English border could absorb no more water and ‘erupted’, or suffered a ‘bog burst’. Having reached saturation point, and with virtually nothing tethering it to the land underneath, part of it simply slid away. It became a floating island of peat moving down a gentle slope for a couple of days until it finally formed an adjunct to its old self, which was left between 10 and 30 feet lower than previously.

In Peat: Its Use and Manufacture (1907), authors Frederick Gissing and Philip Björling suggest that ‘peat’ first came into common usage in English following reports of this event, the word previously having been used only in Scotland and northern England, whilst ‘turf’ was used in the south and Ireland. The Oxford Dictionary of English Etymology suggests the origin is Celtic, while the Collins English Dictionary suggests: ‘C14: Anglo-Latin peta, perhaps from Celtic; compare Welsh peth thing’.

Whilst the natives of central and southern Scotland and latterly the English simply knew it as ‘peat’, the Gaels had a whole lexicon for describing its differing natures, textures and uses. It could be a material for burning in the hearth, or a watery mire; sometimes it was the summer pasture of cattle, at other times the pit from which a sinner’s soul could only be rescued by the Word of God.

Whatever the name, the same scientific principles for understanding what a bog is apply in every language. Bogs are composed of waterlogged peat created by sphagnum mosses. The structure of these plants acts like a sponge, retaining rainfall and making it difficult for other vegetation to grow, for, unlike other plants, sphagnums need very little nitrogen or minerals to survive. They create a paradise for themselves but one which forms from layer upon layer of decaying mosses. This gradually turns into peat at the very slow rate of about one millimetre per annum. These self-perpetuating conditions are so favourable to the mosses and so unfavourable to normal soil being formed – there are only minute amounts of decaying plant debris for worms, fungi and chemicals to feed on – that it allows for virtually no other plants to grow.

Studies indicate that most bog development began 5,000 to 6,000 years ago, but some are considerably older at 9,000 to 15,000 years. How deep a peat bog is can be extremely variable, with around 1 to 3 metres being the average for blanket bogs, and raised bogs around 5 metres, but it is generally accepted that a bog needs to be a minimum of a half-metre deep. The planning permission for small-scale commercial peat extraction at Tomintoul in the Cairngorms specifies that cutting must stop at this depth to allow the bog to stand a chance of recovery.

Cool, wet and, usually, oceanic climates are ideal for the formation of peat bogs, which explains why in Scotland 13 per cent of the land area (approximately one million hectares) is covered in bog. This is predominantly in the north and west of the country, but there are also significant areas in the eastern uplands too. There are massive peat bogs at this latitude from Russia through to Canada and in northern Europe, particularly around the Baltic, but peat is also found in warmer, wet climates under jungles in Africa and Indonesia.

Raised bogs are predominantly Lowland; blanket bogs, Highland. In a raised bog poor drainage encourages the growth of layer upon layer of sphagnum, which can absorb eight times its own weight in water. As the layers grow, the surface of the bog rises and rises, often forming a dome, swollen up like a pregnant belly. These Lowland bogs suffered in the eighteenth century as agricultural improvement began to be introduced; they were drained to create farmland as the Industrial Revolution saw population growth.

Kirkconnel Flow near Dumfries and Flanders Moss are examples of Lowland raised bogs, while Rannoch Moor in the West Highlands and the Lewis moors in the Outer Hebrides are typical blanket bogs. Local subtleties of geography make for no hard and fast rules for where bogs are created or even the types of bog plants growing in them, but what is clear is that bogs need poorly drained land in which to form, with the amount of water going into the bog exceeding the amount of water escaping. Given Scotland’s climate, this can be at high, as well as at low, altitude, with wet enough conditions in troughs high up between peaks being as conducive to sphagnum mosses as they are across the vast flat plain of the Caithness and Sutherland Flow country.

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Kirkconnel Flow is typical of many raised bogs. It is 98 per cent water and 2 per cent organic matter. The major vegetation is sphagnum moss and cotton grass. Formed 10,000 years ago, it would have grown from pits and depressions left after the last glaciers retreated. As the pits filled with vegetal matter, the sphagnum mosses grew and layer upon layer gradually separated themselves from the land and water around and beneath them, and became almost entirely dependent on rain for nutrients. This type of growth is called ‘cloud fed’ or ombrotrophic. It is a self-contained hydrological unit, enclosed by hills and outcrops, with very low quantities of nutrients for vegetation to grow except above it. The lagg fen plants and trees growing round the bog’s fringes take most of the inflowing nutrients for themselves, so you have this contrast of huge solid trunks of Caledonian pines and silver birches surrounding a moor made up of tiny, delicate waterlogged mosses.

As my wellies sink further into the peaty water, I take a look around me. It’s mid-morning and we are suitably kitted out in waterproofs and wellies, heading into Kirkonnel Flow. In the lagg fen birch trees fringe the bog and a willow warbler is invisible but for its song, which starts with a high note then descends as it progresses. Two buzzards wheel overhead, gliding, one in wide circles, the other tighter, but with an amazing gracefulness. A roe deer stands motionless in the woods fringing the bog. Cabbage white butterflies dance drunk on the pale spring sun. In contrast, the talk is of black ravens, appropriate in this transitional place that is neither water nor firm land. In so many legends they are the messengers between worlds.

My friend Dave had invited me to join this group led by his colleague, Dr Lauren Parry of Glasgow University, to take some core samples from this peat bog near Dumfries. From these cores, palynology, the study of pollen samples, reveals a hidden world that is both biological and historical.

One of the group, Michael, asks, ‘Have you smelled a young raven’s feathers? They smell of brimstone and fire!’ (Unknown to us we are about to hear of a geological Hades very soon.)

I think of Tollund man, a body found in a Danish bog, a sacrificial victim, and his watery transition to another world.

Michael is going to help ring the young ravens in their nest, but when asked where will not divulge the location – they are still in peril from farmers and gamekeepers.

Out on the Flow the flimsy coring tool used by Dr Parry to dig down into the bog is like a thin spade attached to a metal tent pole. It is of Russian design – the Soviets carried out a large amount of research on their huge peat reserves when isolation and Cold War politics forced them to look within their own lands for fuel and warmth. It is thrust down into the moss, then rotated to extract longitudinal samples of peat, then retrieved. Different depths are reached by the simple addition of another metre of tent-pole shaft.

The blade of the corer slips smoothly into the flesh of the bog down about 30 cm through the living top 20 cm or so of the bog, the acrotelm, and into the start of the catotelm, the layers of dead plant material. Here we are not only looking at distance in terms of centimetres but also in terms of time: this first core goes back about 150 years. Organic material tends to decay quicker in this level because it is more exposed to the atmosphere than in the deeper layers, where oxygen is absent. In it can be found evidence of man’s activity – fly ash rich in carbon from industrial processes spewed from factory chimneys and coal- (and peat-)...